In computers and other electronic systems and devices, there may be a need to inform a Power Management Controller (PMC) about a Power Management Event (PME) that may require attention. A PME may occur, for example, when a user presses a key on a keyboard or moves a mouse, in order to “wake up” a computer or a monitor from “sleep mode” or power-saving mode. Another example of a PME is receiving an incoming transmission by a modem or a facsimile operating, e.g., in “idle” or “stand-by” mode.
Applications and devices based on PME-related transmissions may be used, for example, in networks, servers, desktop and mobile computers, wireless communications devices, cellular devices, and high-speed interconnects; for example, an Ethernet controller may restore operation of a system from a “sleep mode” upon receipt of a predefined network transmission.
PME signals initiated by multiple Peripheral Component Interconnect (PCI) devices may be merged and routed as a single input to a PMC, for example, by tying together communication wires, e.g., in a “wired-OR” configuration. Power management software may perform a network scan to locate the originating device or devices. However, actual implementations, for example, some operating systems, may fail in performing the scan across multiple devices and/or across multiple data buses. As a result, the PME-related transmissions of each PCI bus are routed separately, resulting in decreased system efficiency, increased pin count and compatibility problems.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.